The primary objective of the research is to investigate the use of organotin compounds as potential insecticides and/or larvicides against the Anopheles mosquito, the primary vector of the parasite responsible for human malaria. The development of an effective insecticide and/or larvicide would be of tremendous value in the effort to reduce the spread of this highly debilitating and often deadly disease. To accomplish this objective, organotin compounds will be tested for their effectiveness against mosquito larvae, adult female mosquitoes and mosquitoes infected with Plasmodium berghei, a rodent specific malaria. Larvicidal screening will involve placing mosquito larvae and various concentrations of the organotins together for 24 hours and determining the toxic effects of the organotin compounds. Three methods will be used to determine the effects of the organotin compounds on adult female mosquitoes. The first method involves a topical application of the compounds to the thorax of the anesthetized mosquito and determining the effects. The second procedure involves placing adult mosquitoes into cartons that have been treated with the organotin compound of interest for 24 hours. Finally, the effects of the compounds on the malaria protozoan parasite development will be evaluated by following the development of the oocyst and sporozoite stages of Plasmodium berghei, a rodent specific malaria. Subsequently, new organotin compounds will be designed and synthesized with the aim of developing more effective compounds. The proposed research is also designed to provide training for students at the University of the District of Columbia in the research methods currently employed at government, industrial and university laboratories. To accomplish this, students will participate in all phases of the project, from the syntheses of organotin compounds to the toxicity studies involving both mosquito larvae and adult mosquito.